Dishwasher air gap overflows, plumbers stumped

jensenh said: 06-30-07 11:35 AM

Dishwasher air gap overflows, plumbers stumped

When our dishwasher runs, water comes out of the air gap and leaks out onto the counter. This has been happening since we moved into the house a couple of months ago. It's a fairly new house (1999), and the dishwasher is a high-end Miele model.

The amount of water that leaks out is not a huge amount. maybe 1 or 2 cups. I don't think it's the whole amount of water used by the dishwasher.

We had our handyman look at it, he seemed confident at first that he could fix it. He checked the seal of the air gap and decided it was good. So then, he snaked out 20 feet or so of pipe assuming there must be a clog. But there was no clog. He gave up, stumped, and recommended that we

call a plumber.

So, we called the plumber. He spent a couple of hours working on it, snaking through even more pipe (50 ft? Longer? Can't remember.) No blockage in the pipe. He also checked the air gap itself and decided that it looked fine (no cracks, etc.) He charged us > $300 and said "sorry, I can't figure out what's going on" and left.

Now, we're back where we started except poorer. We don't have the money to keep calling plumbers out and paying them $300 a piece hoping someone will eventually figure it out. So I'm hoping someone here might have an idea to help us.

One idea my wife has is that maybe the construction of the air gap doesn't quite have enough space to deal with the high pressure drain from the Miele dishwasher. Is this a possibility? Other ideas?